Can someone recommend a vendor who sells narrow (3/16"-1/4" wide) flat wood rasps? My internet searches have not been satisfactory. I see sets of rifflers available but their cut and width are rarely specified. If a set included a medium grain in the right width I would be happy to buy it.
I have been making some keyed miter joints by hand (where a wooden key is inserted transversely). I think these are also called false (faux) box joints. Normally the key is 3/16" - 1/4" thick. I make them by hand, and finish the bottom of the recess with a chisel. Because this is end grain a wood rasp would be quicker and smoother to get a flat bottom.
Doug